<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <script>
    class Person{
      constructor(name,age){
        this.name = name;
        this.age = age;
      }
      say(){
        console.log(`my name is ${this.name}, now ${this.age}`);
      }
    }

    let person = new Person('xiaoming','16')
    person.say();
    console.log(person);
    console.log(person.constructor);
    console.log(typeof person);
    console.log(toString.call(person));
  </script>
</body>
</html>